There are many well known small, hand-propelled vehicles used for manually transporting small loads. One such device is a hand truck having a generally L-shaped body with wheels at the base of the L-shaped body and handles at the top with a small ledge to set objects. Such ledge is typically level with a support surface when the hand-truck is upright. An object to be moved is tilted forward, the ledge is inserted underneath such object, the object is then allowed to tilt back and rest on the ledge. Then the truck and object are tilted backward until the weight is balanced over the large wheels, making otherwise bulky and heavy objects easier to move.
Improvements to such hand-propelled vehicles have been developed over the years. One improvement relates to providing powered lifting, lowering and transporting features. One example of such a prior art device is disclosed in U.S. Pat. No. 6,530,740 issued to Kim on Mar. 11, 2003. Kim teaches a hand truck with an electrically operated lifting platform. While Kim is an improvement over the prior art hand-propelled vehicles, the Kim hand truck does not fully address several problems related to providing a powered hand truck device with powered features; some of which are discussed below. In addition, Kim provides no teachings related to associating an electronic module for providing automatic features to such the system (as described later).
First, while the Kim device does use a ball screw configuration in the powered lifting system, the lifting systems requires the use of rollers that rotate in the up direction but not in the down direction thereby providing a braking feature. What is needed is a system that provides for dynamic breaking and eliminates the need for unidirectional rollers.
Second, the Kim device uses only one vertical lifting mechanism. Thus, there is no redundancy in the lifting mechanism which diminishes safety and reliability as one lifting mechanism is subjected to the entire load. What is needed is a system that provides for a plurality of lifting mechanism that share loading.
Third, the Kim device uses springs to provide for a counter balance. What is needed is a system that does not require such springs.
Fourth, Kim (an not known similar prior art device) does not provide for an electronic module for providing a plurality of features including: automatic weighting of a package, automatic warning when weight of package exceeds a predefined maximum weight value, power supply monitoring and warnings, time stamped data, location stamped data, transport directions, automatic customer information lookup, wireless link to remote computing device, wired or wireless link between a scale and a controller, locking feature, power management and power generation features, imaging features, audio features, and self diagnostic features.